The first targets of the regrettable 1917 Espionage Act were antiwar labor organizers against US WWI conscription. Read the March 1917 cover of the anarchist THE BLAST:   “This man subjected himself to imprisonment and probably to being shot or hanged under the new Espionage Bill
 
The prisoner used language tending to discourage men from enlisting in the United States Army
 
It is proven and indeed admitted that among his incendiary statements were—
 
Thou shalt not kill
    and
Peace on earth good will to men”